Add yeast, warm milk (or water) and 2 tablespoons of sugar in a bowl and whisk properly. Set it aside for approximately 10 minutes so it'll get foamy.
In a large bowl - combine flour, eggs, yeast mixture, butter, salt and 3 tablespoons of sugar. Stir properly until the mixture becomes doughy.
Knead the dough for 5 minutes until it becomes smooth, and transfer the though to a separate bowl covered with cooking spray, and cover it with plastic wrap. Let it rise in a warm place until it doubles (approximately 1 hour).
On a pastry board dusted with flower - roll the dough to 1/4 inch thickness.
Using a drinking glass - cut the dough into small donut circles (about 15). Cover the rolls with a towel and let them rest for 10 minutes.
In the meantime, heat vegetable oil in a saucepan up to 375 degrees.
Place the donuts in the hot oil (5 at a time) until they turn golden-brown on both sides (about 1 minute each side)
Start taking the Sufganiyot out of the pan using a slotted spoon, and let them cool on a baking sheet covered with paper towels.
When still warm, roll the donuts in powdered sugar
Fill a pastry bag with jam (strawberry jam is the most popular choice). If you're a pro Using a toothpick, create a hole in the side of the donut, and fill it with jam.
Tip:If you're serious, you can use a jelly donut filler instead